The SpeedFlex, from Riddell, is the industry's latest attempt to reduce head trauma through technology. It does it with an exterior panel that gives on impact, dispersing the blow. No one expects this to create a concussion-free game, but it may help in some cases. "It's a different scenario for different individuals," says Michael Princip, an engineer who's consulted on helmet designs. "All you can do is account for as many scenarios as you can." Here are the lid's new features.

Face MaskFace masks are connected to the shell with plastic clips, two of which traditionally have been positioned in the forehead area. But the SpeedFlex's upper clips are spaced out toward the temples, letting the mask flex slightly when hit.

Ratchet Chin StrapThe classic snap buttons have been replaced by a mechanical system that functions like a zip tie — pull to tighten and release with the push of a button — to keep the helmet locked in place.

Shell PanelRather than a monolithic design, the helmet has a small horseshoe-shaped opening that lets the panel move slightly inward to absorb hits to the crown, one of the most common impacts. Riddell has sent samples of the helmet to 80 percent of NFL teams.